Introduction: Aneurysmal bone cysts are benign, highly vascular, expandable, and osteolytic skeletal tumors. The prevalence is around 1.4 cases per 100,000 individuals. ABCs represent 1% of all bone tumors and 15% of all primary tumors of the spine. ABSs usually affect adolescents.
Methods: We report a case of a 56-year-old man who presented with neck pain and recent history of traumatic brain injury with no loss of consciousness associated with cervical trauma. Neurological examination was normal. The CT scan of the cervical spine revealed an unstable type II odontoid fracture and a large osteolytic expansile lesion involving dens, anterior body, left lateral mass and left pedicle of C2 vertebra. Magnetic resonance imaging of the cervical spine showed a large, expansile, heterogeneous, multilobulated lesion occupying the axis, mostly on the left side; multilobulated cysts containing fluid-fluid interfaces were observed on T2-weighted images and a blood content of the cystic lesion was suggested by the high T1-weighted gadolinium contrast enhancement. Firstly the patient underwent an occiput to C4 posterior plate-screw-rod spinal fixation in order to reduce the instability of craniocervical junction and prevent further axis compression fractures. Biopsy of the C2 lesion was performed. Immunohistochemical examination established ABCs diagnosis.
Results: After surgery, cervical pain improved and no sensorimotor dysfunction occurred. Selective angiography of the ABC was achieved and feeder vessels were not clearly identified, therefore embolization could not be performed. To date, the patient is waiting for elective surgical treatment of the C2 lesion.
Conclusions: The unusual age of presentation is probably ascribable to an active state of the tumor with progressive and slow growth, but without extravagating anatomic borders (stage 2 according to Enneking classification). Despite its wide predominance among children and young adults, this type of neoplasm should also be taken into account in the differential diagnosis of osteolytic spinal tumors arising in adults.
Patient Care: Improving differential diagnosis of osteolytic spinal tumors arising in adults.
Learning Objectives: The aim of this case report is to present an unusual case of aneurysmal bone cyst of the second cervical vertebra in a 56-year-old patient.